Diamond T 969 fuel cap
 

i havent started restoration of my Diamond T 969 truck as yet as i want to get my 39 Ford 1 ton ute finished first. In the meantime though i have been accumulating the needed parts. My truck is a hard cab with civilian type gauges and the early fuel tank before standardized fuel necks and caps. I'm looking for a cap like this.

fuel cap
 

I think that is a motorbike fuel tank cap . I got NOS fuel caps here from diamond T , and they are standard Diamond caps with a chain and t bar. A friends early diamond also came with these caps, like the ones I have for spare .

Cap
 

The photos above are of a cap from a 969 wrecker owned by a friend of mine. Can you post a picture of the cap you have please Maurice.?

If the truck is early production with "civilian" type gauges, then it would most certainly have the small 2" fuel caps. The larger 4" caps were from 1943 on....

I agree with Maurice, that cap is from a British bike originally and fits a plain tube. As far as I know, all US necks have some sort of bayonet type fitting.

Cap
 

This is the fuel tank in the truck.

If it is not the correct cap does anyone have a picture of one? It screwed in to my mates fuel neck nice and tight so it certainly fitted properly.

fue cap.
 

I will take a picture as soon as I am there .
The Diamond 980 981 kept a small filler neck till the end .

fuel cap
 

one on an early civy dash Diamond , and onother NOS one

The filler neck measures 75mm o/s diameter.

Cap
 

I received the cap from Maurice and it is to fit a 2 inch neck. No good for my truck. The neck on my tank is 3 "/75mm. I believe my tank is original, (the bottom is rusted out) and it is identical to an early 969 of John Belfield's. Still looking for answers. And a cap. (PM sent Maurice.)

fuel cap
 

The fuel tank neck must have been changed at one time , the Americans only had 3 sizes , 2 fuel cap sizes , all early ones were 2", 980/981 stayed that way , and the bigger one , the 3rd was a radiator cap size .
looked at the Matchles in our collection , and that has a 75mm neck with your cap on .

fuel cap
 

Last picture shows Matchles tank cap.

cap
 

Thanks Maurice. Just for interest can you get a close up of the inside of the Matchless cap and the neck. I had another look at my tank and you can see from the above picture that the neck on mine is at the edge of the tank pointing out on an angle and not on the top flat part of the tank. I cant see anywhere where the 2" neck would have been removed and the hole blanked off, but I haven't removed the tank either as yet so I don't know what else could be revealed under the tank guard/step panel.

fuel cap
 

G3L picture attached

cap
 

Thanks Maurice. No doubt about it now. Those caps are definitely the same. Now the question is why would Australian Diamond T's have had a change of fuel tank? (Talking about two I know of and waiting on someone to check the wrecker at Bandiana). And why would you change to a motor cycle tank neck and cap? Especially since the standardized tank of later war years had the four inch cap. I know some of the Australian Diamond T's with the early civvy gauges had the gauge holes blanked off and re cut to take the standard military gauges.

I was in Bandiana
 

Jack, I was in Bandiana for work and stopped in to the museum to photograph the Ford WOT and took some pics of fuel caps for you.
The museum Diamond T fuel fillers are all the same and there a 2 types/variations of caps, but all the same diameter and locking lugs/tangs.
Checked both the wreckers and tank transporter.

caps
 

Thanks Darrin.

Seems they also have had a change of fuel gauge sender

cap
 

Jack, how close is a blitz cap, ?.

caps
 

Bob, I've got a new cap from Maurice. What I need now to change the tank back to original is a filler neck. The early jeeps had a two inch neck as did Studebakers so I have learned.